Acids, Bases and Salts

• Acid


  Substance that, when dissolved in water, increases the concentration of hydrogen ions (H+ ions)
• Arrhenius acid


  Covalent compound that does not contain H+ ions in the pure state, but forms H+ ions when dissolved in water
• Ionization


  Process in which individual positive and negative ions are produced from a molecular compound dissolved in solution
• Base


  Substance that, when dissolved in water, increases the concentration of hydroxide ions (OH- ions)
• Arrhenius base


  Ionic compound that separates into ions when dissolved in water, yielding OH- ions
• Dissociation


  Process in which individual positive and negative ions are released from an ionic compound dissolved in solution
• Arrhenius acids


  • Have a sour taste, change blue litmus paper to red, and are corrosive to many materials
• Arrhenius bases


  • Have a bitter taste, change red litmus paper to blue, and are slippery (soapy) to touch
• Brønsted–Lowry acid


  Substance that can donate a proton (H+ ion) to some other substance
• Brønsted–Lowry base


  Substance that can accept a proton (H+ ion) from some other substance
• Hydrogen ions in an aqueous solution do not exist in the free state but react with water to form hydronium ions (H3O+)
• Any chemical reaction involving a Brønsted–Lowry acid must also involve a Brønsted–Lowry base
• Conjugate acid-base pair


  Two species, one an acid and one a base, that differ from each other through the loss or gain of a proton (H+ ion)
• Conjugate acid


  Species formed when a proton is added to a Brønsted–Lowry base
• Conjugate base


  Species that remains when a proton is removed from a Brønsted–Lowry acid
• Water can act as either a Brønsted acid or a Brønsted base, depending on the circumstances
• The autoionization of water is an equilibrium process
• pH


  Negative logarithm of the hydrogen ion or hydronium ion concentration in molarity (mol/L)
• pOH


  Negative logarithm of the hydroxide ion concentration of a solution
• Significant figures in logarithm


  Number of digits after the decimal place is equal to the number of significant figures in the original number
• Acid-base neutralization reaction


  Chemical reaction between an acid and a hydroxide base in which a salt and water are the products
• Volumetric analysis


  Procedure to determine the concentration of an acid or base solution using a neutralization reaction
• Acid-base titration


  Neutralization reaction in which a measured volume of an acid or base of known concentration is completely reacted with a measured volume of a base or acid of unknown concentration
• Acid-base indicator


  Compound that exhibits different colors depending on the pH of its solution